#pragma once
#include <iostream>
#include <string>
#include <cerrno>
#include <cstring>
#include <cstdlib>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <functional>
#include "Log.hpp"
#include "InetAddr.hpp"

enum
{
    SOCKET_ERROR = 1,
    BIND_ERROR,
    USAGE_ERROR
};

const static int defaultfd = -1;
using hander_message_t = std::function<void(int sockfd, const std::string message, const InetAddr who)>;

class Udpserver
{
public:
    Udpserver(uint16_t port, hander_message_t t) : _sockfd(defaultfd), _port(port), _isrunning(false), hander_message(t)
    {

    }

    void InitServer()
    {
        // 1. 创建 udp socket 套接字
        _sockfd = socket(AF_INET, SOCK_DGRAM, 0);
        if(_sockfd < 0)
        {
            LOG(FATAL, "socket error, %s, %d\n", strerror(errno), errno);
            exit(SOCKET_ERROR);
        }
        LOG(INFO, "socket create success, sockfd: %d\n", _sockfd);

        // 2.0 填充 sockaddr_in 结构
        struct sockaddr_in local; // struct sockaddr_in 是系统提供的数据类型， local 是变量， 在用户栈上开辟空间。
        bzero(&local, sizeof(local));
        local.sin_family = AF_INET;
        local.sin_port = htons(_port); // port要经过网络传输给对面，先到网络，_port：主机序列->网络序列，转成网络序列
        // a. 字符串风格的点分十进制的IP地址转成 4 字节IP
        // b. 主机序列，转成网络序列
        // in_addr_t iner_addr(const char*cp) -> 同时完成 a & b
        // local.sin_addr.s_addr = inet_addr(_ip.c_str()); // "192.168.3.1" -> 字符串风格的点分十进制的IP地址 -> 4字节IP
        local.sin_addr.s_addr = INADDR_ANY; //htonl(INADDR_ANY)

        // 2.1 bind sockfd和网络信息(IP(?) + Port)
        int n = bind(_sockfd, (struct sockaddr*)&local, sizeof(local));
        if(n < 0)
        {
            LOG(FATAL, "bind error, %s, %d\n", strerror(errno), errno);
            exit(BIND_ERROR);
        }
        LOG(INFO, "socket bind success\n");
    }

    void Start()
    {
        _isrunning = true;
        while(true)
        {
            char message[1024];
            struct sockaddr_in peer;
            socklen_t len = sizeof(peer); // 必须初始化成为sizeof(peer)
            // 1. 要让server先收集数据
            ssize_t n = recvfrom(_sockfd, message, sizeof(message) - 1, 0, (struct sockaddr*)& peer, &len);
            if(n > 0)
            {
                message[n] = 0;
                InetAddr addr(peer);
                LOG(DEBUG, "get message from [%s:%d]: %s\n", addr.Ip().c_str(), addr.Port(), message);
                hander_message(_sockfd, message, addr);
            }
        }
        _isrunning = false;
    }

    ~Udpserver()
    {}
private:
    int _sockfd;
    //std::string _ip;
    uint16_t _port; // 服务器所用的端口号
    bool _isrunning;
    hander_message_t hander_message;
};